My aunt's work is done. Can I seal her to her parents before their work is done?
Here is the information from the Knowledge Article:
Vicarious ordinances performed out of sequence are valid, but they become effective only after the prerequisite ordinances are completed.
The FamilySearch Family Tree website enforces the correct order of individual ordinances: baptism, confirmation, initiatory, and endowment.
It is preferred that sealings be done after individual ordinances, but it is not required. Family Tree does not enforce the order of sealings for deceased persons. A deceased couple can be sealed before their individual ordinances are done. Likewise, a deceased child can be sealed to deceased parents before the parents are sealed and before the parents’ individual ordinances are done.
If a sealing ordinance was done out of order, you should simply make sure that the rest of the ordinances get done. You do not need to report the issue to FamilySearch Support. Nor do you need to redo the sealing. The sealing becomes valid after the individual ordinances are done.
Is your aunt your parent's sister? Then you should complete your grandparents' work, including sealing them as a couple, before sealing your aunt to your grandparents.
Is your aunt your parent's brother's wife? Then you should not do any work for her parents because you are not related to them but you can and should complete her sealing to parents so that her ordinances are complete.
This is according to Ron Tanner's 2019 Rootstech presentation, "What's New on FamilySearch (for members of the church)" at: https://www.rootstech.org/video/whats-new-on-familysearch?lang=eng starting at 38:50.
I am just another 'lowly' User/Patron ...
[ And, I happen to be a Member of the Church ... ]
Just in passing ...
You can ...
I hope, that this may also help/assist, somewhat.